The Sample Distribution and Banking Core (Part A) serves to provide clinical bone marrow, pheresis and peripheral blood sample to the various projects. A well established system is in place with centralized sample, collection, processing, processing, distribution, banking, and databank/record keeping. Samples are processed to yield serum, protein whole cell lysates, DNA, RNA, cells, and granulocyte fractions. A shift to perform magnetic antibody cell sorting (MACS) to separate leukemic from non-leukemic cells was recently implemented thereby allowing the core to provide a purer production. Dependent on project requirements, fresh or stored material is delivered to all projects and cores B and C of this grant. Protocols for the equitable distribution of scare materials are also in place. The core maintains an up to date database of all the materials that are available to the overall project database. The core maintains an up to data database of all the materials that are available that is attached to the overall project database. Project investigators can search this database over the secured network to identify available archival material of interest. The Cell Culture Core (Part B) will provide cell culture support for this Program Project. The assays we use can detect hematopoietic progenitors at various levels of differentiation and can distinguish between normal and neoplastic colony-forming cells. These assays are well suited to address a major issue arising in this program project, namely the derivation of the cells responding to various specific agents investigated in this PO-1 on normal Vs leukemic early and mature progenitors. We will use the in vitro assays to determine the effect of specific kinase inhibitors as outlined in Project 1) on leukemic and normal (early an mature) progenitors. We will also use the experimental system to test the in vitro effects of various nucleoside analogues and without kinase inhibitors and inhibitors of Cdk2 phosphorylation as presented in Project 3. The Cell culture core will also support the work proposed in Project 4 by examining whether genetic abnormalities detected at locus 7q31.1 exist both in early and mature progenitors. Dr. Zeez Estrov will direct part B and Steven Kornblau will direct part A and serve as overall core director.